Method of treating fermentation-gas.



PATENTED APR. 28, 1903.

J. F. WITTEMANN.

METHOD OF TREATING EERMENTATION GAS.

APPLICATION FILED MAR. 16, 1900.

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PATENTED APR. 28, 1903 J. F. WITTEMANN. V METHOD OF TREATING FERMENTATION GAS.

APPLICATION FILED MAR..16, 1900.

3 SHEETS-SHEET 2.

N0 MODEL.

Evita many PATENTED APR. 28, 1903.

J. F. WITTEMANN. METHOD OF TREATING FERMENTATION GAS.

APPLICATION FILED MAR. 16. 1900- 3 SHEETS-SHEET 3,

N0 MODEL.

mowed UNHE Srarrns Artur rricn.

THE WITTEMANN COMPANY, OF N NEW YORK. i

EW YORK, N. Y., A CORPORATION OF METHOD OF T REATING FERMENTATlON-GAS.

SPECIFICATION forming part of Letters Patent No. 726,487, dated April 28, 1903.

Original application filed December 31, 1898, Serial No. 700,808. Divided and this application filed March 16, 1900. Serial No. 8,991. (No specimens.)

To all whom it may concern:

Be it known that LJAooB FREDERIO WITTE- MANN, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and usefullmprovements in Methods of Treating Fermentation-Gas; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable to others skilled in the art to which it appertains to make and use the same.

The present invention relates to methods of treating fermentation-gas to prepare it for the purpose of enlivening, vivifying, etherizing, and flavoring fermented beverages or liquids after their fermentation'has subsided and they have become quiet or flat and have settled to brightness by resatu rating the same with the most desirable part of the gas received from fermentation,together with volatile ethers carried over with such gas, the same being the product of their own fermentation or of that of a similar beverage.

My invention also relates to method for effecting a thorough and complete amalgamation of the gas, others, and beverage by refrigerating the combined gas and ethers to a low temperature suffioiently below the temperature of the beverage so as to condense the same and cause them to be more readily absorbed by the liquid. While various methods have been employed for reenlivening such beverages, as by the addition of pure carbonic-acid gas or by resaturation with previously-liquefied gas taken either from the same beverage during its fermentation or from similar fermenting liquids or with such gas compressed without regard to the retention therein of the volatile ethers commingled o therewith, it is found that such merely reenlivened beverages lack the natural agreeable tonic flavor and taste possessed by beverages which have been allowed to undergo a secondary fermentation under pressure, the result either of a sufficiently long storage pe riod to allow the remaining yeast-germs to develop and cause such refermentation or of the addition of yeast and of so-called yeastfoor in the shapeof fermentable sugar or of a certain percentage of the same or of a ;0 similar beverage while yet actively fermenting. The latter method is the one generally in use and known in the brewing industry as kraeusening and bunging. It entails a heavy expenditure for strong casks, requires a great deal of attention to the progrose of the refermentation and reclarification, and, finally, great care in drawing the bright beverage off the sediment of spent yeastcells, many of which, nevertheless, remain 6o suspended in the beverage, owing to the high tension or pressure under which it has to be held to insure the usually high degree of saturation with gas demanded. The introduction of these kraeusen (a mixture of worts and yeast just beginning to ferment) also necessitates the use of finings, usually gelatinous substances, and of chips, usually of soft wood, to offer an increased surface to the yeast to settle on. Such chips are very 7o liable to impart a foreign taste to a beverage or tocontaminate or impair its fine flavor in casethese chips are not thoroughly sterilized. As the first fermentation of the kraeusen introduced (usually from ten to twenty per cent. of the bulk) is suppressed through the gas-pressure generated in and on the beverage, a certain percentage of the fermentable sugar of such kraeusen and many yeastcells are retained in the finished product, although it may temporarily have become bright, even brilliant, in appearance. Such kraeusened beverages therefore will not retain their condition long, especially when subjected to changes of temperature, and at all times are sure to refermentas soon as consumed and to cause a certain harmful disturbance of the digestive organs, their continued inflation with gases, acid reaction of the stomach, and similar undesirable symptoms. Such kraeusening of otherwise ripe and wholesome beverages requires a new period of storage, additional cooperage room, attention, and in the case of beer and other sparkling beverages also additional 5 refrigeration. To overcome all these objectionable features, as well as to effect a material saving in the manufacture, is the chief object of my invention, which provides for resaturatin g the flat beverage with fermentation-gas whose exhilerating ethers are preserved in their original state, notwithstanding compression to which the gas is subjected.

As my improved method will mostly be applied to the manufacture of beer, (lager,

ale, and porter,) I shall hereinafter use the term beer as indicative of the entire class of beverages and similar liquids to which my invention is or may be applicable.

In carrying out my invention I rack off a sufficient quantity of beer when the same is in active fermentation in an ordinary fermenting-vat and has raised a solid head, usually called kraeusen, and after it has been skimmed, agitated, or reaerated, as may be deemed necessary, such quantity of fermenting beverage is conducted into one or more closed casks tight enough to stand a reasonable pressure, which may vary from one pound up to about ten pounds above that of the atmosphere, such vessel being filled to within a short distance of its top. The fermentation of the beverage being in active progress, the remaining space in said vessel soon fills with the gas of fermentation, which displaces any air contained in the same, the air escaping through a suitable vent through the open bung-hole. The absence of air from the escaping gas can readily be detected by its odor. The vent-is closed when the gas has become air-free and connection made to a gas-conduit leading to a compressor, this conduit preferably having been previously freed of air, either by a liquid or gas entering from the bottom upward. The compressor may be of any ordinary construction, but with sufficient clearance to allow the carrying along with the gas to be compressed of a sufficient quantity of cooling liquid to absorb the heat generated by the compression of the gas, and should preferably also have the compression-cylinder surrounded by a cooling-jacket. Fermentation-gas being saturated with ethers,(usually about one-half per cent.,) such ethers either diffuse or change their nature under the heat generated by the ordinary means of compression, whereby a peculiar (mostly repulsive) flavor is imparted to beverages charged with fermentation-gas. Cooling on the outside of a compression-cylinder having proven insufficient to obviate this, I feed a variable proportion of refrigerated water with the gas at each stroke of the compressor, and as this water must be free of air and has to feed into the compression-cylinder against the pressure of the gas-supply I preferably carry it back from the discharge-receiver to the compressor, means being provided for refrigerating the said receiver, as by placing it within a refrigerated room or by providing a refrigerating-coil within the receiver or otherwise subjecting it to the action of a refrigerating medium. As the compressor discharges into said receiver pressure is gradually raised in the same and the cooling liquid forced back into the feed side of the compressor under the full pressure developed within said receiver, communication being provided between such receiver and one or a series of storage-tanks to receive the dry gas after it has separated from the cooling liquid. This receiver preferably also constitutes a purifier or gas-washer by reason of the combined discharge of compressed gas and cooling-water, the latter.passing through the body of gas accumulated within the reservoir in a fine shower at each stroke or delivery of the compressor, absorbing volatile acid vapor, which usually is in mixture with fermentation-gas as it arises fresh from a fermenting beverage. As the cooling-water thus used as a purifying medium accumulates in the bottom of the receiver it is recooled and gradually returned to the inside of the compressing-cylinder and used over again. After the cooling liquid becomes saturated with acid orother organic gases and becomes non-absorbent it is discharged through adrain provided at the bot- .tom of the receiver and is replaced bya fresh supply of purifying liquid. I preferably employ plain pure water as the cooling and washing medium; but any other liquid or solution may be used for the same or additional purposes, such as destruction of germs, if desired to absorb any other admixture of the fermentation-gas.

My practical experiments have shown that to effect a complete saturation of beverages with the recovered fermentation-gas, so as to combine the two elements as well as is done by the refermentation method usually employed, it is necessary to have the gas at the time and point of saturation at a somewhat lower temperature than that of the beverage to be saturated, that such lower temperature allows of a low saturating (carbonating) and racking pressure, saving much or all loss of gas and of wasteliquid; butI have also found that fermentation-gas in which fermentationethers have remained in undisturbed condition cannot conveniently be cooled in the necessary low temperature to make it fit for absorption by beverages except when kept at a pressure exceeding ten atmospheres for a length of time (usually about one day) in one or more tight containers and has a comparatively low and uniform temperature and that such gas,though compressed and rexpanded, does not lower its temperature over a fraction ofa degree for every volu me it expands. The present invention therefore further provides for speedily and conveniently efiecting the ICC necessary refrigeration of fermentation-gas,

cooled to the proper temperature in a con taining vessel, can be withdrawn, preferably from the bottom of the latter, and the pressure within said vessel allowed to gradually diminish, or else a fresh supply of gas may be supplied into its top, so as to gradually displace the cooler gas which discharges from the bottom outlet. I preferably provide communicating pipes connecting a series of such gas-storage tanks at both the top and bottom, each connection between such communicating pipes and the tanks being equipped with a suitable valve, so that the inlet or outlet of each tank may at any time be put into communication with the respective inlet or discharge pipe or shut off from the same; but I may also make a continuous connection between such tanks, connecting the bottom outlet of one with the top inlet of the next communicating tank,,thus forming, in effect, one continuous container and providing for gradual displacement of the cooler "as contained therein by the fresh supply or-warmer gas. Each tank is provided at the top with a vent and at the bottom with a drain for the purpose of exhausting air previously contained therein and of drawing off any condensation from the same. In order to completely displace the air from such tanks before they are filled with the gas, I first fill them completely with practically air-free Water and then displace this water by the gas entering at the top, discharging the water through the bot-.

tom drains.

In saturating liquids with fermentation-gas thus prepared I provide a connection between i the storage tank or tanks and a separate apparatus or carbonator, causing the gas before entering the carbonator to first pass through a pressure-reducing valve,.next (but not necessarily) through a moisture-absorbing device,

pensed with except the pressure-reducing valve,which serves to maintain within said saturator or carbonator a supply of gas at a predetermined regular pressure. Usually I also provide a gas-attcmporating device, such as a pipe-coil submerged under a warming liquid or a steam-jet or gas-flame, for the purpose of preventing the freezing of the gassupply valve or regulatoiythe gas preferably being made to expand into the carbonator at a temperature below or at the freezing-point of water.

which the gas-pressure is maintained, preferably by about two to live pounds, and in entering it first passes a supply egnlating valve, which is controlled by a rod communicating with the balanced support of an overflow-tank, the latter being in communication with both top and bottom of the saturating apparatus, so that the liqnid-level within the.

The beverage to be saturated is. supplied under a pressure exceeding that at carbonator is indicated by said overflow-tank and the liquid-supply controlled. thereby. The overflow-tank is preferably made of a horizontal pattern, so as to cause a slight variation in the liquid-level to have a quick action on the liquid-supply valve.

The invention is further characterized by an arrangement whereby the action of the compressor is controlled by the pressure of the fermentation-gas on the supply side of the latter, whose governor is operatively connected with pressure-regulated devices.

In order that my improvedmethod may be fully understood, I have represented suitable apparatus in the accompanying drawings, in which Figure 1 represents, chiefly in side elevation, an apparatus for carrying out the invention, certain parts being shown broken away and in section. Fig. 2 shows the lower portion of the saturator or carbonator enlarged looking from the right of Fig. 1, with some parts broken away and others in section. Fig. 3 is a sectionalized side elevation of a portion of the compressor-cylinder and some adjacent parts, showing the connection for the cooling liquid; and Fig. shows the receiver in front elevation, together with. a series of gas-containers or storage tanks somewhat differently arranged than those appearing in Fig. 1. Fig. 5 is a view of the compressorgovernor in side elevation with some of the parts broken away andin section.

Referring particularly to Fig. 1 of the drawings, A represents the ordinary kraeusen form of closed fermenting vessel or cask, in which active fermentation is in progress. These casks are connected to a feed-pipe a by short valved pipes A in order to form, a common connection between said casks. The pipe (1 leads from the fermenting-vessels and being shown as extending horizontally and connected by a suitable union with a safetyvalve m and with a vertical pipe-section a, which is in turn connected by a union a with a short horizontal section a entering the side of the cylinder b of the compressor A The said compressor A is of the wellknown double-acting type, so that at each stroke of its piston b (see Fig. 3) a charge of gas will be drawn into the cylinder from the fermentation-casks, while anothercharge previously taken in on the opposite side of the piston is being compressed and discharged through pipe d. In furtherance of the chief object of my invention a pipe 0 is arranged to communicate at the point 0 (see Fig. 3) with the compressor-cylinder, this pipe being shown as a branch of a pipe o which communicates with a supply of refrigerated liquid, so that with each stroke of the piston b a charge of this refrigerated liquid will be injected into the compression-cylinder with the gas through a conduit b leading thereto. The mixture of gas and liquid is discharged from the compressor-cylinder through the pipe d, which extendsthrongh a vertical wall 6, dividing the compartment in which the compressor is located from a compartment B,

which is maintained at a very low temperatureby any suitable means. Within this cold compartment a tankf rests upon the floor near the partition e and constitutes a receiver for the mixture of gas and liquid, the pipe (1 entering the top of said tank and communicating with a nozzle d, which is slitted or perforated, as at 01 so as to subdivide the commingled gas and liquid, whereby a washing effect is had as the liquid discharges in a shower of fine spray through the body of gas within the receiver. The liquid collects in the bottom of the receiver, and I preferably extend a pipe g fromthelowerportionof thereceivertoathreeway valve 0 with which communicates the auxiliary liquid-supply pipe 0 so as to provide for circulating the supply of cooling liquid until it becomes non-absorbent. As hereinbefore stated, the object of this circulating system is to provide for conveniently maintaining the liquid at a low temperature, this being effected by its collection in the bottom of the receiver, which is located in the cold room, and also to keep it under a sufiicient pressure to insure its being injected into the compressor-cylinder with the gas which is under pressure as it' comes from the fermentation-vats. It will be understood that the accumulation of gas in the receiver will eventually exert a pressure on the collection of liquid in the bottom of the receiver sufficient for this purpose. As hereinbcfore stated, the receiver falso constitutes a gas washer or purifier by reason of the mixture of gas and liquid being discharged therein in subdivided form, the liquid passing through the body of gas in theform of fine spray, absorbing the volatile-acid vapor usually in admixture with fermentation-gas which arises of storage-tanks it rest side by side upon the floor of the cold room B, the bottom of the first tank being connected with the top of the second tank by a pipe h and the bottom of the second tank being connected with the top of the third tank by a pipe 72/ so that these tanks form, in effect, one container. The first tank of the series is connected with the top of the receiver f by a pipe f which enters the top portion of said storage-tank, and the bottom portion of the last tank of the series has an.outlet-pipe h fitted to its lowest portion and designed to convey the gas toasaturating apparatus. Each of the tanks 7?. has an air-vent 77, at the top and a draincock k at the bottom. Gas-pressure in the tanks can be read by a gage 71 which is connected by a pipe 72. with the first tank of the series, said gage being mounted in a panel, also containing gages a and f connected by pipes f and a with the union a and the receiver f, respectively.

The saturating apparatus which I preferably employ comprises a tank 2', into the top of which a pipe 2" enters to supply the fiat beer or other beverage to be recharged and out of the bottom of which leads a pipe i for drawing off the charged liquid. This pipe 1? leads to a racking-compartment, where the finished beer is to be racked into packages for the market. A suitable filter A is incorporated in the pipe i intermediate its connection with the saturator and the racking compartment. The pipe 2' extends horizontally into the rackingroom, where it is supported at a suitable height above the floor on a rack A, suspended from the ceiling, a sight-glass 2' being mounted upon said rack and forming a part of pipe 17. From this pipe extends branch supplypipes A and to said pipes at their lower ends are connected flexible branch pipes A ,the

lower ends of the latter being adaptedto enter the bung-holes of the packages to be filled with the finished beer. All of these branch pipes are suitably valvedfor regulating the supply of beer to the packages. A constant head of liquid is maintained within the tank t', preferably by means of a horizontally-disposed floatingcylinder'i,communicatingwith both the top and bottom of the tank by pipes i and 2' and suspended from one end of a lever 71 by a chain a, the opposite end of the lever being formed for adjustment thereon of a counterbalancing-weight 2' and connected by a rod j with a valve j in a casing 7' (see Fig. 2,) with which the pipe 2" communicates. A fiat-beer-supply pipe 76 also communicates with this casing through an elbow is, upon which is mounted a sight-glass k and a pressure-indicator Intermediate of the flatbeer-supply tanks A and the saturating apparatus a pressure-regulator A of ordinary construction, is incorporated in the pipe is for the purpose of supplying beer under proper pressure to the saturator. The gas-pipe h joins the casing of an expansion-cock h, from which a smaller pipe It leads to a casing m, having a gage m mounted thereon and apressure-reducing valve on" contained therein. This casing is in communication with a filter 'n, and a pipe-section 'n leads from the latter into the top of the carbonator-tank 1;, a gage n being mounted upon said pipe-section and also a thermometer n By means of the gages above mentioned. the gas-pressure can be accurately determined, and with the thermometer in communication with the gas-conduit the pressure and temperature of the gas entering the carbonator are predetermined. The mixture of this gas with the fiat beer, or, in other words, the saturation of the latter with gas, takes place in a well-known way, the

beverage being supplied under a pressure somewhat. exceeding that at which the gas is maintained and said beverage being discharged into the carbonator-tank in subdivided form.

, ing the pipes 0 and the pipes 0 being provided with valves 0 so that the tanks may be independently charged withgas. The arrangement for discharging gas from the tanks is of a similar nature, comprising a pipe 19, extending horizontally along the three tan ks and having branches entering the lower portions of the tanks and connected with said pipep by unionsp', containing valves 19 In this last-described storage arrangement there is a gage q for each tank, such gage being located in front of the tank and connected with the top thereof by a pipe (1 A common drain-pipe 0' extends along underneath the tanks, connecting with the interiors of the latter by means of valved unions 0*. The vent connection 7& is in this case extended down to within convenient reach of the operator, as at it.

In order that the action of the compressor may be regulated by the initial gas-pressu re or the pressure of the fermentation-gas on the supply side of the compressor-cylinder, the governor of the compressor is equipped with a fiuid-pressure-regulator attachment of the following description: A bracket 3 is mounted upon the frame of the governor and supports a horizontally-disposed cylinder 3', one end of which is formed with a port 8 communicating with a pipe 8 which connects with the union a", and thus establishes communication between the fermentation-gas conduit and one end of the cylinder 8'. Within the latter there is a piston 75, (or it might be a diaphragm,) whose rod is cou-, pled to one arm t of a bell-crank lever pivoted to the bracket 5 and having its other arm 15 extending between the shoulders on the stem to of the valve which controls the supply of motive fluid to the compressor, said stem having the usual connection with the governor-balls to. For purposes of tensioning adjustment a screw 2 is entered through alooss formed upon. the,bracket s, and a spiral spring ,2 is interposed between the inner end of said screw and the upper side of the bell'crank lever, as clearly shown in Fig. 5.

It will be seen that by the arrangement above described the supply of motive fluid to the compressor will be regulated by the gaspressure in the conduits leading from the fermentation-vats to the compressor-cylinder, such pressure operating upon the piston 15 and through the connection described controlling the valve-stem to, so that upon an increase of the fermentation-gas pressure the valve-stem will be moved in a direction to close the valve and upon a reduction ofsuch gas-pressure the piston will be moved back by the governor-balls.

The manner in which the process of my present invention is carried out by the form of apparatus above described with reference to the drawings will be understood from the statement of invention preceding the description, so that no further explanation is considered necessary. Of course it will be understood that this process might be performed by other forms of apparatus than that here shown. Therefore the appended claims are not confined to any particular form of means for carrying out the invention.

I lay no claim herein to the apparatus employed in the practice of my improved method, since said apparatus is claimed in my pending application filed December 31, 1898, Serial No. 700,808, of which application the present case is a division.

Having thus fully described my invention, what Iclaim as new, and desire to secure by Letters Patent of the United States, is-

1. The improved method of recoveringfermentation-gas, the same consisting in supplying gas from a source of fermentation under more than atmospheric pressure,- intermingling air-free refrigerated liquid with the gassupply,..maintaining such liquid in association with the gas during compression of the latter, discharging the commingled liquid and gas into a receiver under refrigeration, separating the liquid from the gas, and returning the liquid to the gas-supply under pressure.

2. The improved method of recovering fermentation-gas, the same consisting in supplying gas from a source of fermentation under more than the atmospheric pressure, intermingling air-free refrigerated liquid with the gas-supply, maintaining such liquid in association with the gas during compression of the latter, discharging the commingled liquid and gas into a receiver under refrigeration, separating the liquid from the gas, and returning the liquid to the gas-supply under pressure of the accumulation of gas in the receiver.

3. The improved process of recovering and cleansing fermentation-gas, the same consisting in supplying gas from a source of fermentation under more than atmospheric pressure, intermingling airfree refrigerated liquid with the gas-supply and maintaining such liquid in association with the gas during compression of the latter,discharging the com min gled liquid and gas in subdivided form into a receiver, and there separating the liquid from the gas, the liquid being showered through the accumulation of gas in the receiver.

4:. The improved process ofrecovering and cleansing fermentation-gas, the same consisting in supplying gas from a source of fermentation under more than atmospheric pressure, intermingling air free refrigerated liquid with the gas-supply, and maintaining such liquid in association with the gas during compression of the latter,discharging the commindischarging the comrningled liquid and gas into a receiver under refrigeration, separating the liquid from the gas, and again commingling the liquid with the continuous supply of fermentation-gas previous to its compression, returning the liquid to the gas-supply under pressure of the gas in the receiver, and then storing and refrigerating the gas.

In testimony whereof I affix my signature in presence of two witnesses.

. JACOB FREDERIC WITTEMANN. Witnesses:

A. H. MCARTHUR, Oscoon H. DOWELL. 

